Number Sense Blog

Meteorology: Sunny with a 100% Chance of Math

As a young equestrian, Danielle Gersh became obsessed with how the weather affected her horses. Will the temperature dip low enough so that they’ll need blankets? Will the rain cause them to slip in a muddy riding ring?

Gersh’s horsemanship earned her an equestrian scholarship at Southern Methodist University, where she studied convergence journalism. There, she experienced first-hand the exciting and highly unpredictable nature of Dallas’ weather, from heat waves and severe thunderstorms, to hail and the occasional tornado. Gersh was hooked, and her next career move became obvious: Become a meteorologist and television weather forecaster.

Radar image of the deadly tornado in Moore, Oklahoma, not far from where Gersh was interning in 2013.

“It’s All Math”

Meteorology, the study of the atmosphere and its phenomena, requires understanding and using mathematics, as well as physics and chemistry. Gersh admits that she wasn’t a particularly strong math student when she went on to study meteorology at Mississippi State. Fortunately, a talented and patient meteorologist she worked with also became her tutor for math, teaching her how to calculate derivatives.

“Growing up, I always loved observing weather patterns, but I was never fully aware of the correlation between meteorology and math,” she said. “Had I known, I definitely would have studied harder in school!”

Now a meteorologist and reporter for CBS2 and KCAL9 in Los Angeles, Gersh uses math every day.

“Forecasting requires the use of everyday math on so many levels, from averaging together computer-generated model data, to observing temperature differences in distinct atmospheric strata, and even calculating the probability of rain or snow,” she said.

She analyzes and interprets radar and satellite images, charts, and graphs.

“I incorporate knowledge about topography and our microclimates here in California and spend a lot of time looking at temperatures. It’s all math.”

Technology Revolutionizes Forecasting

In earlier decades, forecasters did their calculations by hand, which was tremendously time consuming. Computer technology has made forecasting far simpler and quicker. Today’s forecasters use numerical weather prediction, in which supercomputers crunch giant datasets of weather observations from land, sea, air, and space.

“It’s a lot of really intricate math, but the computers really help you. You don’t need to be a math genius, but you do need a genuine interest in understanding,” she said.

Gersh works hand-in-hand with meteorologists at the National Weather Service (NWS), a sub-agency of the National Oceanic and Atmospheric Administration (NOAA). The NWS assists local forecasters across the U.S. by disseminating forecasts, warnings, and data.

“I used to work in Boston, and when you’re forecasting nor’easters [non-tropical cyclones], it’s so much math. For example, snow-to-ice ratios: how much snow you’ll get from different amounts of water. Depending on how much moisture is in the air, that changes. On the East Coast, we ask, is it a “fluffy” or “wet” snowfall? We would even have a “fluff factor” for our viewers for making snowballs and stuff. We also had a “frizz factor” for your hair—should you wear a ponytail or a hat?”

Surface analysis of severe weather from Texas to Pennsylvania.

A Life-Saving Profession

But forecasting isn’t all snowballs and ponytails; it’s a critical responsibility. The public depends on television weather reporters for warnings about severe weather events that could result in injury or death, such as fire, flood, or freezing rain. Weather forecasts also assist homeowners in knowing when to bring their livestock indoors, line their homes with sandbags, board up their windows, or when (and how) to evacuate.

In California, where Gersh now works, forecasting is particularly crucial during fire season. Firefighters have to plan their attack according to temperature, wind direction and speed, dew point, and relative humidity. First responders, from ambulance dispatchers to swift-water rescuers, and every level of government, depend heavily on forecasts in order to prepare for—and react to—major weather events.

Such an event occurred in 2014, when a “700-year-storm” hit the Palm Springs area of California, where Gersh was working at the time. Two years’ worth of rain fell in the course of a single hour. The mass flooding that resulted was dangerous: It takes only six inches of rushing water to knock a person off their feet, and 12 inches to sweep away a small car.

Live water vapor map of the Western United States.

“During severe weather, more deaths occur due to flooding than any other storm-related hazard,” Gersh said. “Many occur in automobiles as they are swept downstream.” Gersh and her team’s storm coverage helped viewers prepare for the danger in advance and urged them to stay indoors as the flooding began. They were later nominated for an Emmy Award for their continuous coverage of the storm and the destruction it left behind.

As weather forecasting has become more advanced and accurate over the years, it has reduced the number of weather-related fatalities. Forecasting’s role in saving lives is increasingly important, as scientists expect more frequent weather extremes to occur under climate change.

Collect Data Globally, Predict Locally

Although Gersh’s forecasts rely on sensors across the world to gather and process data, weather is ultimately a Iocal affair. So, her news organization obtained an SUV with a rooftop weather station that could collect data while driving the local streets. The CBS2 Mobile Weather Lab monitors temperature, wind speed and direction, dew point, rainfall rates and barometric pressure—live on location.

“It’s unique because, while we typically rely on weather stations in fixed locations, the Weather Lab gives us the ability to gather meteorological data anywhere we can drive! It features an LED crawl on top of the SUV to display the weather information it collects. It’s a fun tool!”

Bringing cutting-edge technology and information directly to the public excites the weather-obsessed broadcaster.

“I think passion can overcome any test or challenge you face. I didn’t love math growing up and certainly wasn’t a top math student. But, applying it to something I am truly passionate about totally changed my perspective—and I wouldn’t be where I am today without it!”

Meteorological Specialties Are Numerous

Young people who are interested in weather or climate (the average of the weather over time and space) may not realize that broadcasting is only one of many career options. Below is a list that may get them thinking.

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